As is well known, trucks or trailers of the van type, with open rear doorways, are backed into cooperation with building doorways for loading and unloading. The width of the truck bodies is usually the same standard width as that of the building doorways. It is desirable to seal out the weather, when loading and unloading, and dock seals commonly in use are of the type embodying a compressible body of square or rectangular cross-section. To insure that the rear edges of the trucks engage these compressible bodies, they must be so disposed that they overlap or extend into the doorway. This, reduces the size of the passageway between the building and the truck. Also, air and water usually becomes entrapped within the cover on the compressible body of this type of seal, and interferes with compression and expansion. Furthermore, it is usually difficult to remove and replace these compressible seals.